Electrode and electrolytic condenser



Jan. 1, 1952 J. B. BRENNAN ELECTRODE AND ELECTROLYTIC CONDNSER FiledJune l5, 1948 26 /L/ZO $25 INVENToR. dwf/Af 15PM/M4N ATMP/VHS PatentedJan. l, 1:3952

ELEGTRGDE'AND ELECTROLYTIC GONDENSER Jos'ephi B. Brennan, Cleveland,Ohio Application June 15, 1948', Serial No'. 33,042

(Cl. V75- 315) 4i Claims.

. had been based upon an application that. was a continuation-inepart'ofmy' previous Patents Nos.

2,104,018 and 2,280,789.

Heretofo're, there have been' various types of construction' proposedfor' electrodes for electrolytic condensers'an'd such constructions havegenerlly been designed sofas to provide as large an amount" of surfacearea on the anode electrode as" possible'so' a'st'o' increase thecapacit-y of a v'giveirsize electrolyt'ic condenser;

The general object of the present invention: is toprovide a novelanodezelectroue construction for a2. condenser and toprovideanel'ectrolytic'` condense'ihavng ai high" capacity fora given vol'- ume.

Another'ob'ject ofthe 'invention' to` provide en" impro-vedelectrodewhich is"` of inexpensive, easily forment construction:

' Another object' ofthe' invention is" to provide electrodes wherein theanode is` of about double tllearea' of the' cathode.

-Yet another object of the invention is' to sub- Stantl'ally encompassVa cathode by the anode in an eletrolytlc condenser' Y VThe""foregoing"and otherl objectsand advantages or, the invention will be made'apparentas the`r specification proceeds.

Attention isY now directed to the accompany ingf` drawings, wherein:

1' ls a. transverse section through apa'ir" of ccndenserelectrodesembodying thev principles of the invention; i

Fig. 2 is a transverse section,I toa reduced scale, through a portion ofan electrolytic condenser macebyuse of thelectr'odes of Fig. 1;

.F.ig. 3 is a transverse section;-y similar to Fig. 1 of a modificationof the invention;

vPig". 4 is" a' transverse sectionV of the electrodes of Fig. 1 with aterminal tab being "shown connected to the anode;

Fig. 5 is an elevation of a strip used in making an anode oftheinvention; Y

isla cross-section oi another type oilv a piftially shaped elestrode Vofthe invention; and

Fig-. 'lisa sect'ono'fthe electrode of Fig. 6 when completed.

Reference will'now be had. tothe details of theconstruction disclosed inorder to describe the invention completely. l The. drawings: disclose anelectrode construction generallyindicated by the numeral IB and such anassembly comprises an elongate, porous, metallic anode I I, the lateralmargins I2 and I3 of which are folded inwardly of the anode If! topositions substantially parallel to the. flattened. center portion Aofthe anode I I. In actual physical iorn'i, the anode II would have. amoreirregular surface than is shown in the drawings and it. also may be ofless uniform thickness and. resemble the electrode of Figs. 6 andv '1.Fig. 1 clearly shows that the free longitudinally extending edges of thelateral portions or margins I2 and I3 of the anode arespacedtransversely of the electrode assembly and this structure is preferredalthoiigh, in some instances, it may be possible that the portions I2.and I3 may be overlapped o1l but-ted. kWhile the folds in the anode I`Iare shown as being made with the adjacent surfaces being. at rlghtanglesto each other., it will be appreciated that in actual practice,l theselfolded. zones of the anode, which. obviously will extend. the length ofthe anode, may be of a more rounded contour. A cathode I4, usually ofslightly less width than the folded anode II', isreceived within anenclosure produced from the lateralV margins I2 and I3 with theremainder of the anode. Conventional insulation strips, or spacers I5and I6, usually made from paper, are positioned between the adjacentsurfaces of the cathode I4 and the anode I I? so as to preventelectrical contact therebetweenand permit impregnation of. the electrodeassembly with electrolyte.

In making a condenser from the electrode assembly I0, the electrodeassembly usually is helically coiled upon itselfl and prior to rollingor coilingthe electrode assembly on itself, additional insulation orspacerl strip Il of conventional constructionis associated withtheelect-rode so-as to separate portions of the anodewwhich wouldlotherwise be in direct contact after a coil is. made from the electrodeIII. In some instances, it may be desirable to produce a stacked'electrode from the electrode IIlby merely superimposing a plu.- ralityof.. short lengths of saine with each ofthe terminal tabs such aconstruction being connected to one ofthe electrode components of each.short length of' electrode in the electrode stack.

Figs. l and 2 clearly bring out that the anode II has approximatelytwice the external surface areaof the cathode I4. Inasmuch as the anodeI I is of a porous construction, ions may freely move through the anodewhen flowing through the condenser, and the relatively large` surfacearea of the anode for a given space fory a condenser made therefrom,will provide a condenser having larger capacity than other types of`cmodensers heretofore made.

The anode IIV is shown as made from porous metallic material adapted.for electrode use, such as spray deposited aluminum sheet.. Also,separate spacers are shown provided between the anode and the cathode,but it may be possible to provide an insulation or spacer coatingdirectly on the surface or surfaces of the anode I I and avoid the useof separate spacer elements. This type of an anode con-struction isdisclosed and claimed in my copending application Serial No. 774,197.Use of such material in making the anode would facilitate thefabrication of the electrode I and assembly of a condenser madetherefrom.

Fig. 3 shows a modication of the invention wherein an electrode assembly20 is disclosed in which an anode 2`I is provided with lateral margins22 and 23 that are folded inwardly of the anode and are superimposed onone surface of the anode. In this instance, the cathode 24 may be of diesame width as that of the foldedan anode and the cathode is positionedexternaly of the anode whereby a spacer strip 25 may be positionedintermediate the center portion of the anode 2|' and the lateralmarginal portions 22 and 23 thereof. A second spacer strip 26- ispositioned between the outer surfaces of the adjacent porticns of theanode and the surface of the cathode 24 which is thereadjacent. With anelectrode assembly as shown in Fig. 3, an auxiliary spacer 2l would alsobe associated with the electrode before ceiling the electrode uponitself or otherwise making a condenser from same. While any conventionaltype of a terminal tab may be provided for the cathode I4, Fig. 4 showsa separate terminal tab 3I that is provided for the anode II and issecured thereto Iin a desired manner. In this instance, holes 32 areshown where the metal has been displaced for staking the anode I I tothe terminal 3|. It will be noted that the holes 32 engage with both thebase or center portion of the electrode II and also with the lateralmargins I2 and I3 of the anode so as to facilitate current flow to andthrough the anode. If necessary, special recessed portions may beprovided in the edges of the cathode I4 to facilitate bonding the anodeII to the terminal tab 3| without contacting the cathode.

Impregnation of electrodes made in accordance with the teachings of theinvention with electrolyte may be facilitated by making longitudinallyspaced apertures in the fold zones of the anode. Fig. 5 shows anelongate porous metallic strip 4I which is to be used in producingy ananode such as the anode II, and this metal strip 4I is provided with aplurality of longitudinally spaced apertures or holes or slits 42therein. These apertures 42 are made in two longitudinally directedrows, each of which is adjacent a lateral margin of the strip 4I.V Theapertures 42 are so positioned that they are located in the fold zoneproduced in the strip 4I when turning or folding the lateral marginsthereof inwardly of the strip so as to produce the folded lateralmargins such as are shown at I2 and I3 in Figs. 1 and 2. Hence, whenelectrodes made therefrom are impregnated with an electrolyte, theapertures 42 greatly facilitate flow of the electrolyte to the enclosureproduced by folding in the lateral portions of the anode. Longitudinallyfolded porous anodes made in accordance with the invention may be usedwithout these apertures 42, if desired.

It will be seen that the specific manner in which the metal strips usedin making the anodes of the invention are produced, is not material tothe present application and that such strips, which are of a porousconstruction, may be produced in any desired manner. Likewise, aspointed out before, any suitable type of a spacer strip may be used andsuch. strip may be integrally bonded to the anode strip, and in someinstances. might be integral withthe cathode, if desired. The electrodesof the invention are formed from porous metallic strips which are in thevicinity of .003"-.009" in thickness and which are several inches wide.The spacer strips normally are thinner than the metal strips.

Figs. 6 and 7 show a relatively uniform thickness electrode 5I that isformed from a porous metallic base strip 52. The strip 52 is of thegeneral shape of a broad isosceles triangle so that Aby folding therelatively thin edge sections of the strip longitudinally in on thecenter part of the strip a relatively uniform thickness electrode isproduced. The strip 52 is of the type produced by spraying metal onto abase that is moved by a spray device. Usually the strip 52 would 'beformed to provide a surface insulating coating before lit is shaped tomake the electrode 5I therefrom. f

While two complete embodiments of the invention have beendisclosedherein, it will be appre'-4 ciated that modification of theseparticular embodiments of the invention may be resorted to' withoutdeparting from the scope vof the invention as defined by the appendedclaims.

Having thus described my invention, what ing an elongate strip thecenter portion of which is appreciably thicker than the edge portionsthereof and with the thickness of the strip gradually increasing from afeather-like edge to the center of the strip, both edge portions beingfolded inwardly upon the center portion of the strip' to provide anelectrode of substantially 'uniform thickness in cross-section.

3. An electrode as in claim 2 wherein the strip` is porous andelectrolytically permeable and the edges of the strip are in immediatelyadjacent relation in the electrode.

4. An electrolytic condenser electrode comprising an elongate strip thecenter portion ofv whichis appreciably thicker thanv the edge portionsthereof that are of gradually increasing thickness inwardly of the stripfrom the lateral margins thereof, both edge portions being foldedinwardly towards the ce'nter portion of the strip to provide anelectrode of substantially uniformthickness in cross-section. y

JOSEPH B. BRENNAN.

REFERENCES CITED The following references are of recordv in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 208,665 Muirhead Oct.` 1, 1878 V1,526,664 Dubilier Feb. 17, 1925 l 2,166,180 Ruben July 18, 1939'2,223,173 Haase Nov. 26, 1940 2,297,607 f Blackburn Sept. 29, 1942'2,375,211 Brennan' May 8, 1945 .2,444,914 Brennan July 13, 19482,470,826 McMahon -l May 24, 1949

